2.OA.A Represent and solve problems involving addition and subtraction.
2.OA.A.1 Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings, and equations with a symbol for the unknown number to represent the problem.
2.OA.A.1.a Ability to explore addition and subtraction with manipulatives to build their conceptual understanding (e.g., snap cubes, subitizing cards, tens frames, hundreds charts, number lines and empty number lines)
2.OA.C Work with equal groups of objects to gain foundations for multiplication.
2.OA.C.3 Determine whether a group of objects up to 20 has an odd or even number of members, e.g., by pairing objects or counting them by 2s; write an equation to express an even number as a sum of two equal addends.
2.OA.C.3.a Ability to use concrete materials to model the meaning of odd and even numbers.
2.NBT.A.1.e See 2NBT1a&b for additional skills and knowledge that are needed for this Standard
2.NBT.A.1a Understand the following as a special case: 100 can be thought of as a bundle of ten tens -- called a "hundred."
2.NBT.A.1a.1 Ability to compose and decompose 100 in a variety of ways lays foundation for regrouping
2.NBT.A.1a.2 Apply the ability to count by tens
2.NBT.A.1b Understand the following as a special case: The numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (x hundreds and 0 tens and 0 ones).
2.NBT.A.1b.1 Ability to count by hundreds using place value manipulatives
2.NBT.A.1b.2 Ability to count by hundreds verbally
2.NBT.A.2 Count within 1000; skip-count by 5s, 10s, and 100s.
2.NBT.A.2.a Ability to skip count within 100 using the hundreds chart and 1000 using the thousands chart
2.NBT.A.2.b Ability to skip-count starting from various numbers (e.g., counting by tens starting with 27)
2.NBT.B.5.b Ability to model regrouping using base ten manipulatives (e.g., base ten blocks, Digi-Blocks, place value arrow cards)
2.NBT.B.5.c Knowledge that when regrouping, the value of the number does not change but the place values of the digits within that number change (e.g., When regrouping the problem 324 – 116, 324 becomes 300 + 10 + 14 in order to regroup)
2.NBT.B.7 Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three- digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
2.NBT.B.7.a Represent addition and subtraction three digit numbers within 1000 using concrete models or drawings and place value strategies, properties of operations, and/or the relationship between addition and subtraction. Then relate the strategy to a written method.
2.MD.B.5 Use addition and subtraction within 100 to solve word problems involving lengths that are given in the same units, e.g., by using drawings (such as drawings of rulers) and equations with a symbol for the unknown number to represent the problem.
2.MD.B.5.a Ability to develop equations to represent word problems
2.MD.B.5.c Ability to justify the reasonableness of their responses
2.MD.B.6 Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the number 0, 1, 2, , and represent whole-number sums and differences within 100 on a number line diagram.
2.MD.B.6.a Ability to locate and represent points on a number line
2.MD.D.9 Generate measurement data by measuring lengths of several objects to the nearest whole unit, or by making repeated measurements of the same object. Show the measurements by making a line plot, where the horizontal scale is marked off in whole-number units.
2.MD.D.9.a Understand that a line plot is a representation of data along a number line
2.MD.D.10 Draw a picture graph and a bar graph (with single-unit scale) to represent a data set with up to four categories. Solve simple put-together, take-apart, and compare problems using information presented in a bar graph.
2.MD.D.10.a Ability to collect, sort, organize and graph data
2.G.A.2.c Ability to apply repeated addition when counting total number of partitions
2.G.A.3 Partition circles and rectangles into two, three, or four equal shares, describe the shares using the words halves, thirds, half of, a third of, etc., and describe the whole as two halves, three thirds, four fourths. Recognize that equal shares of identical wholes need not have the same shape.
2.G.A.3.a Ability to partition circles and rectangles into equal parts lays the foundation for the development of fractions